Portable hand-held computers are typically utilized for data collection and management in the modern computerized business world. For example, commercial transactions for the sale of goods may be stored in a portable hand-held computer that is carried by delivery personnel to a customer's place of business. After the delivery driver enters execution of the transaction into the hand-held computer, an invoice verifying the date, time and contents of the delivery is desired. The invoice may be conveniently printed with a portable printer to which the delivery driver may connect the hand-held computer.
The usefulness of portable printers has been enhanced by efforts in reducing the size and modularity of printers when compared to their respective forerunners. Also, minimization of tasks may further the utility of portable printers by route service people in operating the printers.
Furthermore, it is highly desirable that a portable printing system is adaptable to a variety of environments. Thus, a printer may be mounted in a vehicle in which case it may receive dc power from the power system of the vehicle. Alternatively, it may be desirable to adapt that same printer for portable use wherein the printing system is carried by hand to an interior location such as a warehouse or store in which case it is desirable for the printer to operate from ac power.